TY - JOUR

T1 - Electron hopping integral renormalization due to anharmonic phonons

AU - Majidi, Muhammad Aziz

N1 - Publisher Copyright:
© Published under licence by IOP Publishing Ltd.

PY - 2018/5/9

Y1 - 2018/5/9

N2 - Interpretation of some experimental data of temperature-dependent transport properties of a solid material has led to a hypothesis that some renormalization has occurred to the electron hopping integral, making it decrease as temperature increases up to some limit. Such a renormalization may be attributed to the effect of coupling of electrons with anharmonic phonons. Namely, the presence of anharmonic vibration of two adjacent atoms yields an increase of their equilibrium distance as temperature increases, this in turn weakens the electron hopping integral connecting the two atomic sites. Despite that the above qualitative picture is pretty clear, little has been explored on the detail of how such an electron hopping integral evolves as a function of temperature. Motivated by this issue, here, we propose a tight-binding model incorporating the presence of anharmonic phonons and electron-phonon coupling, and solve it using Green function technique. We define the renormalized electron hopping integral from the band width of the interacting system, and perform self-consistent calculations to demonstrate the evolution of the electron hopping integral as a function of equilibrium distance between adjacent atoms and temperature.

AB - Interpretation of some experimental data of temperature-dependent transport properties of a solid material has led to a hypothesis that some renormalization has occurred to the electron hopping integral, making it decrease as temperature increases up to some limit. Such a renormalization may be attributed to the effect of coupling of electrons with anharmonic phonons. Namely, the presence of anharmonic vibration of two adjacent atoms yields an increase of their equilibrium distance as temperature increases, this in turn weakens the electron hopping integral connecting the two atomic sites. Despite that the above qualitative picture is pretty clear, little has been explored on the detail of how such an electron hopping integral evolves as a function of temperature. Motivated by this issue, here, we propose a tight-binding model incorporating the presence of anharmonic phonons and electron-phonon coupling, and solve it using Green function technique. We define the renormalized electron hopping integral from the band width of the interacting system, and perform self-consistent calculations to demonstrate the evolution of the electron hopping integral as a function of equilibrium distance between adjacent atoms and temperature.

UR - http://www.scopus.com/inward/record.url?scp=85047761062&partnerID=8YFLogxK

U2 - 10.1088/1742-6596/1011/1/012080

DO - 10.1088/1742-6596/1011/1/012080

M3 - Conference article

AN - SCOPUS:85047761062

SN - 1742-6588

VL - 1011

JO - Journal of Physics: Conference Series

JF - Journal of Physics: Conference Series

IS - 1

M1 - 012080

T2 - 2017 International Conference on Theoretical and Applied Physics, ICTAP 2017

Y2 - 6 September 2017 through 8 September 2017

ER -